Radially clamping grips

ABSTRACT

A centrally apertured radially clamping device for angularly immobilizing an object while allowing lengthwise sliding motion thereof, the device having a hollow enclosed cylindrical body containing a plurality of axially extending flexible filaments encircled by a multiplicity of loose pellets substantially filling the cylindrical body.

United States Patent [21] Appl. No. [22] Filed [45] Patented [73]Assignee [54] RADIALLY CLAMPING GRIPS 6 Claims, 1 Drawing Fig.

[52] U.S.Cl 57/59, 57/773 [511' lnt.Cl D0lh7/00, D0lh 13/04 [50] FieldofSearch 57/34,51, 51.5, 59. 60, 77.3-77.45, 106

[56] References Cited UNITED STATES PATENTS 733,299 7/1903 Sui 57/592,908,132 10/1959 Klemmu. 57/59X 3,270,491 9/1966 DeLangen.. 57/77.453,372,537 3/1968 Poullet a1... 57/59 3,408,807 11/1968 Sylthe 57/59Primary ExaminerDonald E. Watkins Attorneys-John R. Bronaugh, George R.Powers and Floyd S.

Levison ABSTRACT: A centrally apertured radially clamping device forangularly immobilizing an object While allowing lengthwise slidingmotion thereof, the device having a hollow enclosed cylindrical bodycontaining a plurality of axially extending flexible filaments encircledby a multiplicity of loose pellets substantially filling the cylindricalbody.

IRADIALLY CLAMPING GRIPS BACKGROUND OF THE INVENTION This inventionrelates to radially clamping grips which exert centripetal forces uponthe periphery of a filiform object while permitting movementlongitudinally. The objects may be textile yarn, fine gage rods, wire orthe like. Grips of this type are disclosed in U.S. Pat. No. 3,372,537for particular use in the manufacture of yarn from textile fibers in aspinning operatron.

In clamping grips of the type described, it is known to have a pluralityof flexible filaments fixedly arranged within the body portion to definean enlargeable aperture therethrough. There has generally been a meanswithin the body portion to damp out vibration of the filaments caused bythe axial motion ofthe object being gripped. The known damping meanshave taken the form ofa sleevelike member positioned around the bundleof filaments and made of a number of resilient materials each havingrelatively high damping power. In some cases, however, the damping powerof such sleevelike members has been inadequate. in the instant inventiondamping means for the resilient filaments are disclosed which overcomethe disadvantages of the sleevelike members by the use of a combinationof damping forces.

SUMMARY OF THE INVENTION The clamping grip of this invention permitsradial expansion and contraction of the central aperture formed by thebundle of inwardly urged filaments, with vibrations being absorbed by amultiplicity of loose pellets which substantially fill the hollowportion of the grip and are in continuous contact with the flexiblefilaments.

It is the general object of the invention to devise a radially clampinggrip of the type described with damping action provided to the flexiblefilaments by a damping mass in the form ofsmall spheroids substantiallyfilling the surrounding area.

It is a further object of the invention to obtain increased dampingaction for the vibrating filaments by the combined forces of a resilientmaterial having high damping power and the frictional restraining forceof the spheroids rubbing together.

It is possible with the damping mass of this invention to control thedegree of damping action by varying the material which forms thespheroids.

BRIEF DESCRIPTION OF THE DRAWING The invention will be described byreference to a specific embodiment as illustrated in the accompanyingFIGURE of drawing which is a view of the grip in longitudinal section.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawing, thegripping device is formed with a hollow cylindrical body 1, closed atone end by an inlet plug 2 having a funnel-shaped orifice 3 as aninletfor the gripping device. A series of flexible filaments 4a to 4i, etc.,is evenly distributed around the axis 5 of the body 1. Each of theflexible filaments is arched at one end so that together they form abow-net, generally designated 6, positioned around the orifice 3. Theother ends of the flexible filaments lie parallel to each other andextend axially to form a bundle, generally designated 7. At the endswhich form the flared part of the bow-net, the flexible filaments areanchored in the bottom ofa circular recess 8 formed in the inlet plug 2and the latter has a height such that its base 9 is at the same level asthe start of the bundle 7. The base 9 is pierced with a hole 10 which isslightly greater in diameter than the bundle 7, so that when an objectis engaged in the grip the bundle 7 is not prevented from expandingradially.

The annular space, bounded by the bundle 7, the inside surface of thecylindrical body 1 and the inlet plug 2, is substantially filled with amultiplicity of pellets 11 which is kept in place by anoutlet plug 12secured to the lower end of the body 1. Plug 12 is provided with a hole13 axially aligned with hole 10. The free end of the bundle 7 extendsinto the hole 13, whose diameter is slightly larger than that of thebundle, to permit radial expansion against the pellets. The hole 13 maybe flared outwardly to allow easy discharge of the gripped object.

The pellets 11 together form a damping mass 14 whose damping power is toa large extent due to the pellets rubbing against one another as thebundle 7 is caused to expand and contract.

It it is required that the mass 14 have solely a vibrationdampingeffect, the pellets 11 can be made of a solid material having lowdeformable properties, such as glass or sand, or of a deformablematerial having low resilience. If, however, the mass is required tohave, in addition to a damping action, a resilient action for boostingthe radial gripping force due to the inherent resilience of the flexiblefilaments forming the bundle 7, pellets made of a readily deformablematerial can be used. The damping power of the mass 14 would, in thiscase, be due partly to the pellets I1 rubbing together and partly to theintrinsic damping power of the material of which the pellets were made.

The pellets ll of the mass 14 should have some yielding property inorder for it to give in when the yarn is introduced in the bundle 7 orwhen the moving yarn has some irregularities. Two cases should bedistinguished. If the pellets 11 are made of elastic material, theirintrinsic yielding property is sufficient, and the entire annularchamber may be filled. If the pellets 11 are made of solid material,their mass 14 must have some play or clearance. In this latter case,there are two possibilities:

a. One can fill the annular chamber incompletely with the pellets, so asto provide some little free space at the top of this chamber. When thegrip rotates, the pellets are indeed submitted to centrifugal forces andthe free surface of the mass 14 approaches the form of a paraboloid aswould be the case with a liquid. The danger with a very high angularvelocity would be that the pellets might rearrange themselves in such amanner that the free space would surround the bundle 7, so that the mass14 would have no more action on it. But in. practice the rearrangementof the pellets under the influence of the centrifugal forces is suchthat the little free space moves toward the top of the bundle 7, nearthe hole 10 at the base of the entrance bow-net, so that the pelletsmaintain their damping action.

b. One can also provide an outer elastic sleeve located between the mass14 and the inner surface of the body 1. In this embodiment, it ispossible to fill the remaining volume entirely up the top of it.

The shape of the pellets should be substantially spherical andconclusive tests have shown satisfactory results with glass spherules ofabout 0.5 mm. in diameter. With pellets of a solid material it isdesirable that the body 1 be of a deformable material to permit therequired intermovement of the pellets. In these tests the clamping gripwas used in a machine spinning textile yarn and it formed the maincomponent of the twisting member of the machine. The clamping griprotated around its axis 5 at high speed and the object being grippedconsisted of cotton fibers which entered the grip through the funnel 3where they were gripped and twisted into yarn before issuing from theend of the bundle 7. The twisted yarn, as it was formed, slidcontinuously along the axis due to the pull applied by a convenientwinding member (not shown).

Textile machinery, in particular spinning, doubling and other likemachines, is one of the main fields of use for grips of this kind,wherein they form part of the twisting or false-twisting operationsprovided in such machines. Other uses can be envisaged, but the objectbeing gripped must be an elongated or filiform object which is requiredto slide lengthwise of the grip while remaining in a fixed angularrelationship therewith. For instance, grips of this kind can be used inmachines for microscrew-cutting from stock in the form of rods of verysmall diameter.

The embodiments of the invention in which we claim an exclusive propertyor privilege are defined as follows:

1. A gripping device for resiliently radially clamping an object whileallowing axial sliding motion therethrough, including a hollow enclosedcylindrical body having a pair of axially aligned holes forming an inletand an outlet for the object, a plurality of flexible filaments securedwithin said body evenly distributed about the longitudinal axis, eachbeing arched at one end so as together to form a bow-net of circularcross section and each having the other end extending axially to form abundle, a damping mass encircling said bundle comprising a multiplicityof pellets substantially filling said body in compressive contact withsaid bundle.

2. A gripping device as set forth in claim 1, wherein said pelletsdefine a toroidal configuration.

3. A gripping device as set forth in claim 1, wherein said pellets aremade of a hard substance lacking readily deformable properties foreffecting damping action through the mutual rubbing ofsaid pellets.

4. A gripping device as set forth in claim 1, wherein said pellets aremade of a readily deformable material having high damping power foreffecting damping action through combining the intrinsic damping forcesof the material with the mutual rubbing of said pellets.

5. A gripping device as set forth in claim 2, wherein said pellets areformed of glass.

6. A gripping device as set forth in claim 3, wherein said pellets areformed of glass.

Dedication 3,584,453.C'Zaude Guignawl, Ferney-V0ltaire, France, and JeanPellaton, Chatelainm and Maurine Poul], Mnyrin, Switzerland. RADIALLY(TLAMPING GRIPS. Patent dated June 15, 1971. Dedication filed Mar. 23,1977, by the assignee, Electrospe'n Corporation. Hereby dedicates to thePublic the entire term of said patent.

[Ofiicz'al Gazette May 10, 1.977.]

1. A gripping device for resiliently radially clamping an object whileallowing axial sliding motion therethrough, including a hollow enclosedcylindrical body having a pair of axially aligned holes forming an inletand an outlet for the object, a plurality of flexible filaments securedwithin said body evenly distributed about the longitudinal axis, eachbeing arched at one end so as together to form a bow-net of circularcross section and each having the other end extending axially to form abundle, a damping mass encircling said bundle comprising a multiplicityof pellets substantially filling said body in compressive contact withsaid bundle.
 2. A gripping device as set forth in claim 1, wherein saidpellets define a toroidal configuration.
 3. A gripping device as setforth in claim 1, wherein said pellets are made of a hard substancelacking readily deformable properties for effecting damping actionthrough the mutual rubbing of said pellets.
 4. A gripping device as setforth in claim 1, wherein said pellets are made of a readily deformablematerial having high damping power for effecting damping action throughcombining the intrinsic damping forces of the material with the mutualrubbing of said pellets.
 5. A gripping device as set forth in claim 2,wherein said pellets are formed of glass.
 6. A gripping device as setforth in claim 3, wherein said pellets are formed of glass.